PHIVOLCS: 339 rockfall, 13 pyroclastic density current events reported in Mayon

More rockfall and pyroclastic density current events as well as sulfur dioxide emission were observed over Mayon Volcano, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) said Friday.

In its 8 a.m. bulletin, PHIVOLCS said Mayon in the past 24 hours had 339 rockfall events and 13 dome-collapse pyroclastic density current events which lasted one to four minutes.

These are higher compared to the 299 rockfall events and seven pyroclastic density current events reported on Thursday.

The sulfur dioxide (SO2) emission from the volcano also increased to 706 tonnes on Thursday from 574 tonnes on Wednesday.

No volcanic earthquakes were observed.

“Alert Level 3 is maintained over Mayon Volcano, which means that it is currently in a relatively high level of unrest as magma is at the crater and hazardous eruption within weeks or even days is possible,” PHIVOLCS said.

A very slow effusion of lava from the summit crater of Mayon Volcano continued to feed lava flows and collapse debris on the Mi-isi (south) and Bonga (southeastern) gullies, according to PHIVOLCS.

The lava flow along Mi-isi gully was extending up to 2.5 kilometers from the summit crater, while the one along Bonga gully was extending up to 1.8 kilometers, the agency said.

Collapse debris has also deposited 3.3 meters from the crater, it added.

A moderate emission of steam-laden plumes that rose 750 meters from the volcano was also observed, drifting to southwest and west-southwest direction.

“It is therefore recommended that the 6-km radius Permanent Danger Zone (PDZ) be evacuated due to the danger of PDCs, lava flows, rockfalls and other volcanic hazards,” PHIVOLCS said.

“Increased vigilance against pyroclastic density currents, lahars and sediment-laden streamflows along channels draining the edifice is also advised, “ it added.

PHIVOLCS also warned that heavy rainfall could generate channel-confined lahars and sediment-laden streamflows in channels where PDC deposits were emplaced.

It added that pilots should avoid flying close to the volcano’s summit as ash from any sudden eruption can be hazardous to aircraft.

Based on the current prevailing wind pattern, PHIVOLCS said ash fall events may most likely occur on the south side of the volcano.

Alert Level 3 in Mayon Volcano was raised on June 8 after three PDC events on the Bonga (southeast) and Basud (east) gullies of the volcano.

NDRRMC

A total of 38,982 people or 10,110 families in 26 barangays in Bicol have been affected by Mayon's activity, the National Disaster Risk Reduction and Management Council (NDRRMC) said Friday.

Of the total number, 18,733 individuals or 5,336 families are staying in 28 evacuation centers, while 1,409 individuals or 402 families are taking shelter in other places.

A total of 1,066 livestock animals were also preemptively evacuated.

A state of calamity was declared in 18 cities and municipalities due to the volcano’s activity, according to the NDRRMC

Assistance worth P85,675,525 has been provided to the victims, it added. — RSJ, GMA Integrated News